ecliptic orbit
71Oort cloud — An artist s rendering of the Oort cloud and the Kuiper belt (inset). Sizes of individual objects have been exaggerated for visibility …
72Tropical year — A tropical year (also known as a solar year), for general purposes, is the length of time that the Sun takes to return to the same position in the cycle of seasons, as seen from Earth; for example, the time from vernal equinox to vernal equinox,… …
73Voyager 2 — For the phone sometimes referred to as the Voyager 2, see LG enV touch. Voyager 2 Voyager spacecraft Operator …
74Halley's Comet — For the video game, see Halley s Comet (video game). 1P/Halley (Halley s Comet) Halley s Comet on March 8, 1986 Discovery …
75Secular variations of the planetary orbits — The Secular Variations of the Planetary Orbits (French: Variations Séculaires des Orbites Planétaires, abbreviated as VSOP) is a semi analytic theory describing the long term changes (secular variation) in the orbits of the planets Mercury to… …
76History of Solar System formation and evolution hypotheses — Capture theory redirects here. For the solar capture theory, see this article s section on Solar System formation. For the lunar capture theory, see this article s section on lunar formation. Ideas concerning the origin and fate of the world date …
77Hipparchus — /hi pahr keuhs/, n. 1. died 514 B.C., tyrant of Athens 527 514. 2. c190 c125 B.C., Greek astronomer. * * * or Hipparchos born , Nicaea, Bithynia died after 127 BC, Rhodes? Greek astronomer and mathematician. He discovered the precession of the… …
78Precession — For other uses, see Precession (disambiguation). Precession of a gyroscope Precession is a change in the orientation of the rotation axis of a rotating body. It can be defined as a change in direction of the rotation axis in which the second… …
79Zodiac — See also: Zodiac (disambiguation) Wheel of the zodiac: This 6th century mosaic pavement in a synagogue incorporates Greek Byzantine elements, Beit Alpha …
80Asteroid belt — For the album by Velvet Chain, see Asteroid Belt (album). The asteroid belt (shown in white) is located between the orbits of Mars and Jupiter. The asteroid belt is the region of the Solar System located roughly between the orbits of the planets… …
